Fluid pump



P. M. GRANT. FLUID PUMP. APPLICATION FILED sarnz's. 1920.

? 0 j y I a Patented May 2,1922.

Jmren 07" STATES PATRICK M. GRANT, OF CHICAGO, ILLINOIS.

FLUID PUMP.

isses.

T0 aZZ whom it may concern:

Be it known that I, PATRICK lVl. GRANT, a citizen of the United States, residing at Chicago, in the county of Cook and State of lllinois, have invented certain new and useful Improvements in Fluid Pinups, of which the following is a specification.

The invention relates to fluid pumps and is shown as embodied in a small pump adapted to be operated by hand for compressing air for pneumatic tires of motor vehicles and other rubber tired carriages and the like.

It is the primary object of the 'pump'to generally improve the construction of the operating parts including the intake and exhaust valve construction, pump base, the pump piston and the handle.

Other objects of the invention will appear from the following description which is directed to the preferred embodiment of the invention as depicted in the accompanying drawing forming a part of the specification, the novel features being more specifically pointed out in the appended claims. o

In the said drawing, Fig. 1 is a sectional view through the handle, the barrel, the piston and the base of the pump taken on line1-.-1 of Fig. 2, the latter being an elevation view of the pump taken at an angle of ninety degrees to the sectional view of Fig.

In both Figs. 1 and 2 a part of the barrel is broken away to shorten the same for illustration, and in Fig, 2 the lower end of the pump barrel is sectioned to disclose details of construction of the p ston.

Figs. 3 and. 1- are top plan and side elevation views respectively of the valves controlling inlet and exhaust ports of the pump.

In the design of the invention it has been the primary object to produce an efficient pump for pumping fluids. and especially air for the purpose of filling pneumatic tires as it is notorious that the average pump and es pecially hand pumps as furnished by motor car nainifacturers at the present time are very inefficient and short lived. herefore, the features of novelty of my improved pump consist largely in certain refinements giving greater efficiency to the parts and enabling them to operate with continued degree of efliciency bver a longer period than devices of this kind as heretofore produced.

Reference character designates the pump barrel which may be constructed of any desired material. as a cylindrical piece of uniformly constructed brass tubing, the

Specification of Letters Patent.

Patented May 2, 1922.

Application filed September 25, 1920. Serial No. 412,760.

extremities of which are preferably screw threaded as at 10 to take the top cap 11 and at 10 to take the base casting 12, the latter like the cap 11 being provided with an enlarged opening screw threaded around its periphery co-operating with the threaded portions 10 and 10 of the pump barrel. For the purpose of providing a fluid tight connection between the lower end of the pump barrel and the pump base casting 12 a gasket 13 is preferably inserted so as to be interposed between the lower end of the barrel and the bottom of the concentric threaded portion in the base casting 12 when,

the barrel is screwed downto position therein. The base casting 12 I prefer to make as small and light as possible as it preferably contains the inlet and exhaust valved passages and is therefore made of an expensive and easily workable material as brass. It has heretofore been common to construct the foot engaging portions of the pump integral with the base casting 12 and where this is done the casting .on account of the metal required becomes expensive and it is frequently not made strong or large enough to bev eilficient anddnrable. For these rea sons I prefer to provide a special foot engaging portion for the base part 12 of the pump,'which is accomplished by construct ing a central downwardly projecting member 12" cylindrical inform and screw threaded to take acentral perforation, which will preferably. be correspondingly screw threaded to form a durable connection, this part being designated generally by reference character 14 and being preferably formed from a suitable metallic channel bar, as illustrated in the sectional view of Fig. 1, and in side elevation in Fig. 2. A suitable locking nut 15 will be screwed in position on the lower or concave side of the channel piece 14, thus effectively and securely fastening the parts of the base together.

The gasket or washer 13, before referred to, of suitable flexible material as fiber, leather or rubber will have a central perforation, as indicated at 13*- registering with the vertical passage 12 in the base casting 12, which latter communicates with a transverse passage 1%, the latter passage extending in diametricallyopposite directions from the vertical passage 12 and terminating in offset or enlarged openings, each screw threaded and designed to furnish housings for accommodating the inlet and exhaust valves and valve seats respectively. The opening constituting the inlet valve housing is surrounded by the screw threads designated by- 12 and the corresponding opening around the housing for the exhaust valve by refer-" ence character 12 The opening or housing for the intake valve is'closed by a screw threaded plug 16, the threads of which cooperate with threads '12 'of the base'castin'g." The plug 16 is provided with an enlarged central perforation 16 designed to accommodate the, stem of the valve clos ng theinlet port of the pump, the valve seat being formedat the inner extremity of the plug'16 as designated by reference character 16*, and being in the form of a peripheral ledge elevated a short distance, as shown in Fig.1,

above the normal face of the end of'the plug whereby an eifective'closure or seat will be endof the stem member 1 7 p p p ta'nce approximating one third the length' thereof and is screw threaded to take the afforded for the flexible portion of the inlet valve. 7 The latteras stated is of special con-'- struction'and is in duplicate5 one valve serving as a closure for the inlet port and another serving as a closure for theexhaustportf The'details of these'valves are shown in Figs 1 3' and 4:, and from an inspection of which it will be seen that'in the preferred form of' these valves a body portion or stem desig-' nated by reference character 1 7 is'provided of some suitable solid: metal as bra ssythe same being angular in crosssection and.

shownas cut from a hexagonal bar. One: 7 is bored for a dis-' suitable threaded screw 1'7R,'the-'latter "being prlovidedwith the usual slot', asindicated; to receive a suitable tool. A val'x' ed'i'sk Sis provided, the same having a central perfora tion adapted to register with the aforesaid: portand tl readed opening in tl'ieend ofthe: h valve stem ihe valve disk 18 is prefer- I ablyprovided at its outer periphery with airgula'rly extending continuous webs, the Web cnone sideof the disk being continuous around the entire periphery of-the disk to furnish aseat for a resilient disk or pad made of some suitable elastic material as leather orrubber composition designed to assist the valve in forming an air tight closure with its sea-t. v

An important feature of inyimproved valve resides in the manner in which I as-' semble the stem member 1.!" and the valve 117 will preferably be about not be injuriously compressed and hence caused to flatten out and gradually lose its efficiency. This construction is obviously beneficial alike for the valve at both inlet and exhaust ports and the valve disk 18 preferably has the outer peripheral flange 0r ledge on the side of the disk opposite the side to which the stem 17 is secured cut away at frequent intervals around its periphery, as indicated at 18 for the purpose of -providing air passages to prevent the valve from'obs'tructing the passage on the dis charge side of the valve when the valve:

is held in the open position. At the discharge side of the passage 12 in the base the valve seat on the baseis indicated by reference character 123, the same being formed similarly to the aforesaid seat16". In [this instance it will be noted that the valve seat is forined integrally with the base casting"12 while the screw threaded plug closing this valve housing at the exhaust passage designated icy reference character 20 is without a valve seat and both plugs 16 and 20 are formed of a length so that there will be an ample space in the valve chamber for freedom of movement "to the valves; T-he valve plug QO likethe plug 16' will be centrally perforated at 20. and the .perfora tion may be screw't-hreaded to take a screw threaded perforated nipple for a fiuidhose designated by reference character 21.

*Theconstruc'tion of the pump pistonwill next be described." I 7 7 LA specially formed or machi.ned piston frame is provideththe same being somewhat smaller in dii'ini'ete'r than tl e internal diameter or hereof the pump barrel l0 and same isdesignate'd generally by reference character This piston constructionis oneo'f the important features of my invention,

which taken together-with other improved features noted enables my improved pump to"o 3erate withmuch greater ease and efiiciency than pumps of this type heretofore produced and'also to be more durable and last much longer in use; The piston frame. 30 is centrally bored and screw threaded to take the threaded lower end of the piston rod 40, the latter passing into the pump bar relthroughthe centrally perforated top cap 11, thesaid'top cap being preferably.perfo rated in the usual manner at 11 to prevent any back pressure on the non-working side of the piston. The pump piston frame in order to be effective is provided with a packing or washer of suitable flexible material as leather, which may be cut from a disk and centrally aerforated to take the piston rod- 1:0 and then formed in suhstantiallv the'shape as indicated by the cross sectional view Fig, 1, this part being designated in the drawing by reference character 31. In order to furnish a suitable seat and housing in the piston for the flexible washer 'o r gasket 31 I give the same a special formation by cutting away the upper surface of the part, as indicated, so that there will be first left a peripheral ridge or ledge 30 surrounding the threaded central opening for receiving the piston rod and onthe exterior of the ledge 3O the material of this part will be cut away a sufficient distance to accommodate the approximate thickness of the pump washer 31, this cutting being in the form of a groove, as indicated at 30 thus leaving a concentric peripheral ridge or rib designated by reference character 30 around the top side of the piston frame. The outer top periphery of the frame 30 on the exterior of the concentric ridge 30 will be rounded so as to permit the downward curvature of the washer 31 and the material of the piston frame number 30 will be turned off or reduced in diameter in a downward direction to a point a short distance above the lower extremity of the piston frame, thus leaving a peripheral lower rib or ledge, as indicated by reference character 30. I For the purpose of securely holding the piston washer or gasket 31 in its normal working position I provide a. circular upper plate 32 which will be of a slightly less diameter than the internal bore of the pumpbarrel so as to escape contact with the walls the pump barrel but at the same time to overlie the flexible piston washer or gasket 31 and retain the saine in its proper workingposition. in assembling the pump piston on the lower end of the piston rod a locking nut of hexagonal or other suitable form indicated by reference character 33 will be first screwed to the approximate upper limit of the lower threaded end of the piston rod 40 and the perforated follower ring 32 which has its perforation larger than the diameter of the piston rod will'be slipped over the threaded part in contact with the nut 33. The piston frame with the flexible washer or gasket 31 in position with the central opening therein surrounding the internal peripheral rib 30 may then be screwed into position on the lower end of the piston rod until the lower end of the rod is brought forcibly into contact'with the bottom of the bored or threaded central opening therein, The locking nut 33 may then be screwed downwardly upon the follower plate which will force the material of the flexible gasket downwardly inlo the peripheral curve 30 in the top of the piston frame and will cause the upstanding peripheral rib 3O to compress and cut into the gasket a certain amount, as indicated in the drawing, so that there will be a bead of material formed in the piston washer or gasket adjacent the upstanding central ledge or rib 30 at the top tending to hold the vasher 31 in position. At the same time the outer periphery'of the washer or gasket 31 will be forced downwardly into the housing formed between the reduced peripheral part of the piston frame and the inner wall of the pump barrel so that in this manner the piston washer or gasket will approximately fill the space between the follower ring 32 around the peripherally reduced part of the piston frame and above the lower peripheral ledge 3O thereof. The, fact that the upper peripheral edge of the piston frame is rounded will prevent any cutting of the piston washer or gasket and it will be seen that the housing for'the active part of the washer thus formed will be very effective in holding the leather or other flexible material, of which this part is made, in its proper working position, so that the only strain that will fall upon this part which receives the hardest usage of any part of a pump will be the duty of frictionally contacting with the wall of the pump barrelas the part is effectively and securely re tained between the follower plate 32 at the top and lower peripheral ledge 30 at the bottom of the piston frame. Furthermore the ledge or central peripheral rib 3W will prevent any undue pressure on the follower plate from cutting or injuring or unduly forcing outwardly the material of the flexible "washer or gasket and the locking rib 3W will *also result in the formation and retention. of the thickened peripheral bead in the flexible washer or gasket at the top thereof, which will tend-to cause the part to remain in its proper working relation dur-,

ing the entire life of the frictional part of the flexible washer or gasket.

Obviously, in order for a pump piston to be effective it must furnish an approXi-' mately complete closure with the walls of the pump barrel on the down or active stroke of the piston and this can only result when the flexible washer or gasket 31 is in contact throughout the periphery of the piston with the pump barrel walls.

me of the common defects in pumps of this character having flexible washers has been. that while the pumps are comparatively new and the gaskets or washers are new there will be satisfactory contact betwecn the piston washer and the pump barrcl but after the pump has been used for a time and the washer tends to lose its elasticity or flexibility the skirt or efiective portion of the washer is found in practice to seat around the piston frame so that the washer may remain entirely or partly out of contact around its periphery with the wall of the pump barrel resulting in leakage and decreased efiiciency in the pump. In order to overcome this defect and difficulty with pumps of this type I provide two improved means which I find in practice insure at all times that the pump washer or gasket will remain in contact throughout its periphery with the pump barrel.

gasket 81 may tend toseat in contact with ,the reduced part of thepiston frame and'recharacter 530 which is cut around the reduced portion of the piston frame about. midwaybetween the upper and lower edges thereof and at a point that falls beneath the skirt or depending portion of the piston washer 31. when the latter is in its proper working position, the groove, however, being cut, so that it will be somewhat above the lower extremity of the washer so that any air pressure within the groove 30' will beeffective to force or crowd the skirt or depending portion outwardly in contact with the pump barrel. I provide a plurality of perforations 30 in the lower end of the piston frame. These perforations 30 are bored approximately parallel with the central opening in the washer frame, which is threaded and takes the piston rod and'theyv each communicate groove 30 -so that as the piston is forced toward the lower end of the pump barrel on:

results that the harder the piston is worked thecloser willbe the. contact as long as the piston washer or gasket remains in effective. working condition; In the use of a piston constructed as described, I have: found in some casesthat'after' the pump hasbeen in use for sometime the flexible washer or main so effectively in contact therewith that even the pressure of the air through the passages 30 and30 might not be sufficient to expand the piston, and my second improved feature consists in the provision of a thin metallic ring or band the material of which is entirely severed at one point in its periphery and will underlie the inner vertical wall of the flexible washer and on the outer periphery of the reduced partof thepiston frame, as indicated by reference character 3-4;, this part being shown in'section in Fig. 1 andin an enlarged perspective in Fig. 5. This ringor band 34 which will be readily erpansible will preferably be made of brass or other suitable non-corroding refined metal so as not to be readily oxidizable will I find be hence effective in preventing sticking of with the peripheral .Another important feature of myl pump" resides .in the construction of the handle which is made of a piece of cylindrical me. talliotubing designated-by reference character 50. -Heretofore handles of this dee:

scriptionhave been attached to pump pistons .by perforatingthe cylindrical handle member and passingthe upper extremity of the piston rod out through the top side of the handle where it issecured in position by suitable'means as a lock nut. This con-.

struction results in placing ,thenut in the upper end of the piston rodin a position where it is in contact with the'hand of the that the upper surface thereof will be smootlniwhich I accomplishby'placing on the interior of the hollow cylindrical han die 50 a cylinder or plug of less length'than the handle as indicated by reference-char-a aicter 51, Fig l the same being boredand threadedas indicated at 52 to take the'upper threaded end of the piston-rod. The plug .5l will preferably be a loose sliding fiton the interior of/thehollow handle member 7 50 and'there willbe an opening in the-wall ofthe cylindrical. member 50 large enough. to permit the upper threaded-end-ofthe piston rod topass readily 'therethrough soi that itmay engage the threaded opening 52 V intheplug 51. Inorder to lock the piston;

rod-and the, handle securely-itogether 'I pre ferto provide a-plate' 53 which m'ay be formedas a special casting to have its upper surface curved to furnish "a seat for the lindrical handle member 50 or if desired, as

illustrated in Figs. 1 and 2, the part 53 may; becut from apiece of channel bar andcentrally bored tofpermittheready passage of the upper threaded end of the piston rod therethrough. The upper thread of the piston rod will be provided with a suitable. locking nut 54; and a springlocking washer. 55 will preferably be inserted betweenthe nut 54 and the plate 53. By this construe tion it will be seen that when the plug 51 is on the interior of the handle the upper end-of the piston rod maybe passed through the perforation in the handle and'into the threaded opening 52 in the plug 51 and screwed into the plug. After this'is done by adjusting the nut 54:011 top of the washer- 55 the plate 53 may be locked inclose contact so that the wall of the handle 50 will be securely held where locked in'position between plug 51 and plate 53 thus giving the handle a rigid attachment with the piston rod which will not have any tendency 1 to work loose in use by reason of the locking character of the washer 55 and the nut 54. At the same time it will be seen that the upper side of the handle will be smooth so as f not .to' injure the hand of the operator.

The improved pump as herein described has been found by me to be highly efficient. It is comparatively economical. to manufac ture and offers advantages not heretofore found in hand pumps used for a variety of purposes in compressing air as for the inflation of pneumatic tire tubes and the like. The fact that each of the scveral parts of the pump are all readily detachable makes it possible for the user ofthe pump to readily replace any worn parts, as for example the pump piston washers, the valve seating gaskets, etc.,' thus adding greatly to the life and effectiveness of the pump.

I claim:

1. In a pump, the combination with a pump barrel of a piston therein, a base memher to which the. said barrel is attached, there being a passageway in the base member communicating with the, pump barrel and valve mechanism in the said passageway comprising a valve seat, a valve stem in cross section adapted tobe guided in said passageway adjacent the valve seat, .a valve plate secured to the said stem, a resilient member carried by the valve plate, and means for locking the said valve plate and stem together.

2. A fluid pump comprising a pump bar rel, a reciprocating piston in said barrel, a pump base secured to one end of the pump barrel, there. being a passageway in, said pump base leading-to an enlarged threaded oassageway intersecting the outer-surface of the pump has, a perforated screw threaded plug adapted to close the said enlarged screw threaded openingin said base, avalve seat carried by the said plug and surrounding the perforation therein, and a valve having a valve stem carried by the perforation in the said plug, the said valve being adapted to co-operate with the said seat on the plug to close the perforation in the plug on the discharge stroke of. said piston.

3. In a fluid pump the combination with a pump barrel of a piston frame having a peripheral groove, a flexible washer surround ing said groove, there being perforations in the piston frame leading from the compression side of the piston frame to the said groove to expand said washer during the compression stroke of said piston frame.

4. In a fluid pump the combination with a pump barrel of areciprocating piston rod in the barrel and a piston carried thereby, the said piston comprising a frame secured to the piston rod, there being a centrally bored piston frame adapted to take the screw threaded end of the piston rod a lock nut on the threaded portion of the piston rod, a pcripheral rib on the piston frame, a perforated follower plate adapted to be secured between the said nut on the piston rod and the said piston frame, and a flexible piston Washer having a central perforation therein adapt ed to surround the said rib on the piston frame and being secured in position between the said follower plate and frame.

5. In a fiui d pump the combination with a pump barrel and a piston rod of a piston 111 said barrel carried by said rod and tornprising a piston frame secured to the said rod, there being *a groove formed periphcrally in said frame for the reception of a flexible piston washer. a washer filling said peripheral groove in thepiston frame, and an opening having one xtremity adjacent the inner wall'of the flexible piston washer and its other extremity on the face of the piston frame adjacent the compression side thereof whereby to expand the washer upon the compression'stroke of the piston.

6. Ina fluid pump the combination with a pump barrel of a piston therein comprising a frame having a centrally bored opening therein adapted to receive a piston rod. there being a reduced portion of said frame adapt ed to accommodate the peripheral edges or skirt of a flexible piston washcr,said piston frame being. provided with a plurality of openings leading fromthe compression side of the piston frame toa groove adapted to underlie the skirt or outer peripheral edge of the flexible piston washer, whereby to expand the latter upon the compression stroke of the piston, a peripheral ledge around the centrally bored openingin the piston whereby to protect the flexible washer, a follower plate and a look nut for cnga ging the threaded portion of :the piston rod to secure the follower plate and the piston rod-to gether and to retain the flexible piston washer in operative relation to the piston frame.

'7. In a fluid pump the combination with a pump barrel of a reciprocating piston rod and a. piston carried thereby and adapted to co-operate with said. pump barrel, said piston comprising a piston frame having a central bore screw threaded to take the threaded end of the piston rod, the body portion of the piston frame being reduced whereby a ledge is formed at the lower edge of the piston frame forming a part of a housing for the piston washer, there being a groove formed peripherally around the reduced part of the piston and adapted to underlie the piston washer together with an air passage leading from said groove to the compression side of the piston frame, whereby the pressure of air on the compression side of the piston frame will tend to expand a flexible piston washer carried around the reduced part of the piston frame, an elastic and expansible metallic ringadapted to overlie the said peripheral opening around the reduced portion of the piston frame whereby to prevent the flexible piston washer from sticking to the piston frame, a flexible piston washer in position around the reduced part of the piston frame, and a follower plate secured on the piston rod in engagement with the said flexible piston washer, whereby to retain the same in its effective operative relation with the piston frame;

8. In a fluid pump the combination with a pump barrel and a piston therein ofa piston rod secured to the piston, a handle for operating the piston rod, a pump base secured to the lower extremity of the pump barrel comprising a casting provided with valved air} passages, a threaded projection or trunnion on the lower edge o f'the casting and formed integral therewith, a foot base member secured to the latter and comthereof through which perforation a thread ed end of the piston rod is adapted to be loosely passed, a plug adapted to be contained in the interior of the said tubular member and having a threaded socket therein adapted to co-operate with the threaded end of the piston rod, and a screw threaded locking device adapted toco-operate with a threaded portion of the piston rod on the exterior of the tubular member to lock rigidly upon the threaded end of the piston rod the tubular handle member and the aforesaid phw therein.

V 10. Ina fluid pump the combination witha pump barrel and a piston of a piston'rod secured to the piston and having theyextremity thereof on the exterior of the pump barrel screw threaded, a tubular handle member provided with} ail-openin in one wall thereof adapted to permit of the insertherein adaptedto register with the opening 1 in the wall of the tubular handle member and to take the threaded end of the piston rod, a perforated supporting member having an opening in the wall of the tubular member and having a concave surface-thereon adapted to co-operate when assembled on the piston rod with the convex outer surface of the tubular handle member, and means for locking the aforesaid plug, the

tubular handle member and the supporting 4 member in rigid relation on the threaded end of'the p1ston rod comprising a spring lock washer and a screw threaded nut below the said supporting member on the threaded upper end of the piston rod. V

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, on thisQOth day of September, A. D. 1920.

I Witnesses; V

CUTHBERT- D. Porrs,

EDYTHE JOHNSON,

PATRICK M. GRAN 

